What Is Wavelength?
Wavelength λ is the spatial period of a periodic wave: the distance over which the wave shape repeats. For a sinusoidal wave it is the distance between successive crests. Relation to frequency f and propagation speed v: v = f λ.
Examples by order of magnitude: visible light 380–780 nm; audible sound (in 20°C air) 1.7 cm–17 m; FM radio ≈ 3 m; microwave-oven radiation ≈ 12 cm; X-rays 10−10–10−8 m.
de Broglie matter waves have λ = h/p. For a 1 kg ball at 1 m/s this is ~10−34 m, vanishingly small. For an electron in a TEM at 200 kV, λ ≈ 2.5 pm — why electron microscopes resolve atoms.
Recent research on this topic from arXiv
Preprints and papers indexed on arXiv.org. Links open the public abstract pages.
- Longitudinal electromagnetic waves with extremely short wavelength
Denis Sakhno, Eugene Koreshin, Pavel A. Belov · 2021 ·arXiv:2103.10205v4
Electromagnetic waves in vacuum and most materials have transverse polarization. Longitudinal electromagnetic waves with electric field parallel to wave vector are very rare and appear under special conditions in a limited class of media, f... - Femtosecond laser-induced sub-wavelength plasma inside dielectrics: II. Second-harmonic generation
Kazem Ardaneh, Mostafa Hassan, Benoit Morel et al. · 2022 ·arXiv:2207.11675v2
Second-harmonic emission at a frequency that is twice the laser frequency is an important diagnostic for nonlinear laser-plasma interaction. It is forbidden for centrosymmetric materials such as the bulk of sapphire. The symmetry, however,... - Short wavelength quantum electrodynamical correction to cold plasma-wave propagation
J. Lundin, G. Brodin, M. Marklund · 2006 ·arXiv:0606098v2
The effect of short wavelength quantum electrodynamic (QED) correction on plasma-wave propagation is investigated. The effect on plasma oscillations and on electromagnetic waves in an unmagnetized as well as a magnetized plasma is investiga... - Variation of Longitudinal Plasma Wavelength under Irradiation and Double Resonance in Coupled Josephson Junctions
Yu. M. Shukrinov, I. R. Rahmonov, M. A. Gaafar · 2012 ·arXiv:1205.6923v1
The effect of electromagnetic wave irradiation on the phase dynamics of intrinsic Josephson junctions in high temperature superconductors is investigated. We predict three novel effects by variation of the radiation amplitude and frequency:...